using System;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        Random random = new Random();

        string[] candidates = new string[]{"Chenling", "Jianan", "Miller", "Renze", "Yanan", "Yishi"};

        string noteMakers = string.Join(", ", candidates.OrderBy(x => random.Next()).Take(4));

        Console.WriteLine(noteMakers);

    }

}